Re: Gather Stats and auto_dop
From: Mladen Gogala <gogala.mladen_at_gmail.com>
Date: Tue, 31 Mar 2020 14:48:34 -0400
Message-ID: <a0adc270-0bad-99cd-5764-0a35816f9544_at_gmail.com>
Date: Tue, 31 Mar 2020 14:48:34 -0400
Message-ID: <a0adc270-0bad-99cd-5764-0a35816f9544_at_gmail.com>
Hi Lothar!
DBMS_STATS doesn't work with auto DOP. That is why you have "degree" argument. Also, DBMS_STATS.AUTO_SAMPLE_SIZE always does full table scan. If there is a monstrous table of 50 GB or more, I set table preference estimate_percent => 1. DBMS_STATS is awkward and I am using dynamic sampling whenever I can, which is usually on data mart/data warehouse configuration.
Regards
On 3/31/20 4:12 AM, Lothar Flatz wrote:
> Hi,
>
> IHAC who is using AUTO DOP (parallel_degree_policy = auto) . It
> does not seem to work with gather_stats.
> Probably because Gather_stats generates a parallel hint.
> What kind of setup would allow gather_stats to use Auto_dop?
>
> Regards
>
> Lothar
>
-- Mladen Gogala Database Consultant Tel: (347) 321-1217 -- http://www.freelists.org/webpage/oracle-lReceived on Tue Mar 31 2020 - 20:48:34 CEST